Heretofore, ISO (International Organization for Standardization)/SMPTE (Society of Motion Picture and Television Engineers) has provided some standards for digital video signals. Of the standards, SMPTE 298M and 335M define meta data indicative of attributes, storage locations, sizes, etc. of material data such as digital video signals for permitting centralized management of the meta data with a meta data dictionary. The meta data dictionary defines several hundred items including titles, staff names, imaging locations, etc. as material data, for example.
Features of materials such as images and sounds, can conveniently be known from meta data about these material signals. Since meta data is uniquely defined by ISO/SMPTE, it has high compatibility and is regarded as greatly contributory to automation of data base management as well as of material exchange between digital apparatuses made by different manufacturers.
Since meta data are basically piggybacked on materials such as video and audio signals, however, in case the video and audio materials are recorded in a recording medium for example, the meta data cannot be read without any playback of the video and audio materials from the recording medium.
On the other hand, in case information about the video and audio materials is generated by actually playing the recording medium for viewing and hearing the images and sounds, it is less necessary to rely on meta data piggybacked on the materials. Namely, the meta data are not used to its full performance.